1. Field of the Invention
The present invention relates to a photo-detector which converts a light intensity to a current magnitude for detection and a photo-detection method using the same, and more particularly to a photo-detector which does not substantially absorb a light to be detected.
2. Related Background Art
A PIN photo-diode and an avalanche photo-diode have been known as a photo-detector which converts a light intensity to an electrical signal for detection.
In such photo-diodes, however, a light to be detected is absorbed and carriers are generated by an energy of the absorbed light. As a result, a substantial portion of the light does not pass through the photo-detector. For example, where the photo-diode is applied to a bus type light communication system which receives a signal light serially by a plurality of receivers, a photo-diode in the first receiver in a communication path absorbs the signal light and the light does not reach the second and subsequent receivers. Thus, each receiver has to newly generate the same signal light as that it received and transmit the generated signal light to the succeeding receiver.